Antimicrobial straw

ABSTRACT

A polymeric tubular conduit including a polymeric tubular conduit wall having an outer tubular layer coaxially overlaying an inner tubular layer which defines a continuous tubular passage along a polymeric tubular conduit length of the polymeric tubular conduit; whereby the outer tubular layer, the inner tubular layer, or combinations thereof, include an amount of antimicrobial agent. The amount of antimicrobial agent can be sufficient to kill or inhibit growth of microorganisms in contact with a corresponding polymeric tubular conduit wall external surface, polymeric tubular conduit wall internal surface, or combinations thereof, of the polymeric tubular conduit wall.

This United States Patent Application is a continuation of U.S. patentapplication Ser. No. 15/469,424, filed Mar. 24, 2017, now U.S. Pat. No.9,955,699, issues on May 1, 2018, which is a continuation of U.S. patentapplication Ser. No. 14/609,319, filed Jan. 29, 2015, now U.S. Pat. No.9,623,229, issued. Apr. 18, 2017, which claims the benefit of U.S.Provisional Patent Application No. 61/933,228, filed Jan. 29, 2014, eachhereby incorporated by reference herein.

I. BACKGROUND OF THE INVENTION

Conventional fluid conveying conduits, whether for conveyance of gasesor liquids, are ubiquitous. The use of fluid conveying conduitsnecessitates handling or contact of the of fluid conveying conduitexternal surface which can result in deposition or placement ofmicroorganisms or other pathogens on the of fluid conveying conduitsexternal surface, which may then be subsequently transferred to othersurfaces or persons.

For example, drinking straws, which are typically open to theenvironment and repeatedly drawn to the user's mouth, can be inoculatedwith microorganisms or other pathogens which can infect or reinfect theuser and, when disposed of, may be handled by other persons or contactother surfaces, resulting in transfer of the microorganisms or otherpathogens to those persons or surfaces.

As an additional example, medical tubing, which may be used to conveyoxygen, liquids, or drugs to a person, can also be inoculated withmicroorganisms or other pathogens. In order for the person to be mobilewhile using the medical tubing, the length of medical tubing extendingbetween the person and the dispensing station is often long. As aresult, lengths of medical tubing may lie along the floor, on bedding,or contact other persons during normal use, thereby becoming a host formicroorganisms or other pathogens which may then be transferred to theuser using the fluid conveying conduit, other persons, or surfaces.

II. SUMMARY OF THE INVENTION

Accordingly, a broad object of a particular embodiment of the inventioncan be to provide polymeric tubular conduit including a polymerictubular conduit wall having an outer tubular layer coaxially overlayingan inner tubular layer which defines a continuous tubular passage alonga polymeric tubular conduit length of the polymeric tubular conduit;whereby the outer tubular layer includes an amount of antimicrobialagent. The amount of antimicrobial agent can be sufficient to kill orinhibit growth of microorganisms in contact with a polymeric tubularconduit wall external surface of the polymeric tubular conduit wall.

Another broad object of a particular embodiment of the invention can beto provide polymeric tubular conduit which forms a drinking strawincluding a drinking straw wall having a drinking straw outer tubularlayer coaxially overlaying a drinking straw inner tubular layer whichdefines a drinking straw continuous tubular passage along a drinkingstraw length of the drinking straw; whereby the drinking straw outertubular layer includes an amount of antimicrobial agent. The amount ofantimicrobial agent can be sufficient to kill or inhibit growth ofmicroorganisms in contact with a drinking straw wall external surface ofthe drinking straw wall.

Another broad object of a particular embodiment of the invention can beto provide polymeric tubular conduit which forms medical tubingincluding a medical tubing wall having a medical tubing outer tubularlayer coaxially overlaying a medical tubing inner tubular layer whichdefines a medical tubing continuous tubular passage along a medicaltubing length of the medical tubing; whereby the medical tubing outertubular layer includes an amount of antimicrobial agent. The amount ofantimicrobial agent can be sufficient to kill or inhibit growth ofmicroorganisms in contact with a medical tubing wall external surface ofthe medical tubing wall.

Another broad object of a particular embodiment of the invention can beto provide a method of making a polymeric tubular conduit, the methodincluding providing a polymeric tubular conduit wall having an outertubular layer coaxially overlaying an inner tubular layer which definesa continuous tubular passage along a polymeric tubular conduit length ofthe polymeric tubular conduit; whereby the outer tubular layer comprisesan amount of antimicrobial agent. The amount of antimicrobial agent canbe sufficient to kill or inhibit growth of microorganisms in contactwith the polymeric tubular conduit wall external surface of thepolymeric tubular conduit wall.

Another broad object of a particular embodiment of the invention can beto provide polymeric tubular conduit including a polymeric tubularconduit wall having an outer tubular layer coaxially overlaying an innertubular layer which defines a continuous tubular passage along apolymeric tubular conduit length of the polymeric tubular conduit;whereby the inner tubular layer includes an amount of antimicrobialagent. The amount of antimicrobial agent can be sufficient to kill orinhibit growth of microorganisms in contact with a polymeric tubularconduit wall internal surface of the polymeric tubular conduit wall.

Another broad object of a particular embodiment of the invention can beto provide a method of making a polymeric tubular conduit, the methodincluding providing a polymeric tubular conduit wall having an outertubular layer coaxially overlaying an inner tubular layer which definesa continuous tubular passage along a polymeric tubular conduit length ofthe polymeric tubular conduit; whereby the inner tubular layer comprisesan amount of antimicrobial agent. The amount of antimicrobial agent canbe sufficient to kill or inhibit growth of microorganisms in contactwith the polymeric tubular conduit wall internal surface of thepolymeric tubular conduit wall.

Naturally, further objects of the invention are disclosed throughoutother areas of the specification, drawings, and claims.

III. BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is an illustration of a particular embodiment of a polymerictubular conduit which forms a drinking straw.

FIG. 1B is an illustration of a particular embodiment of a polymerictubular conduit which forms medical tubing.

FIG. 2 is a perspective view of a particular embodiment of a polymerictubular conduit having an inner tubular layer formed from a firstpolymeric material and an outer tubular layer formed from a secondpolymeric material, the outer tubular layer having an amount ofantimicrobial agent sufficient to kill or inhibit growth ofmicroorganisms in contact with a polymeric tubular conduit wall externalsurface of the polymeric tubular conduit wall.

FIG. 3 is a cross-section 3-3 of the particular embodiment of apolymeric tubular conduit shown in FIG. 2.

FIG. 4 is an enlarged view of a portion of the particular embodiment ofa polymeric tubular conduit shown in FIG. 3.

FIG. 5 is a perspective view of a particular embodiment of a polymerictubular conduit having an inner tubular layer formed from a firstpolymeric material and an outer tubular layer formed from a secondpolymeric material, the inner tubular layer having an amount ofantimicrobial agent sufficient to kill or inhibit growth ofmicroorganisms in contact with a polymeric tubular conduit wall internalsurface of the polymeric tubular conduit wall.

FIG. 6 is a cross-section 6-6 of the particular embodiment of apolymeric tubular conduit shown in FIG. 5.

FIG. 7 is an enlarged view of a portion of the particular embodiment ofa polymeric tubular conduit shown in FIG. 6.

FIG. 8 is a cross-sectional view of a particular embodiment of apolymeric tubular conduit having an inner tubular layer formed from afirst polymeric material, an outer tubular layer formed from a secondpolymeric material, and one or more intermediate layers formed fromadditional polymeric materials, the outer and inner tubular layershaving an amount of antimicrobial agent sufficient to kill or inhibitgrowth of microorganisms in contact with corresponding polymeric tubularconduit wall external and internal surfaces of the polymeric tubularconduit wall.

FIG. 9 is side view of a co-extrusion system adapted for production ofparticular embodiments of a polymeric tubular conduit.

FIG. 10 is top view of a co-extrusion system adapted for production ofparticular embodiments of a polymeric tubular conduit.

FIG. 11 is cross-section 11-11 of the die shown in FIG. 9 through whichmolten first polymeric material and molten second polymeric materialpasses in the production of a particular embodiment of a polymerictubular conduit having an inner tubular layer formed from the moltenfirst polymeric material and an outer tubular layer formed from themolten second polymeric material.

IV. DETAILED DESCRIPTION OF THE INVENTION

Now referring primarily to FIG. 1A through FIG. 4, which illustrateparticular embodiments of a polymeric tubular conduit (1) including apolymeric tubular conduit wall (2) having an outer tubular layer (3)coaxially overlaying an inner tubular layer (4) which defines acontinuous tubular passage (5) along a polymeric tubular conduit length(6) of the polymeric tubular conduit (1), whereby the outer tubularlayer (3) includes an amount of antimicrobial agent (7). The amount ofantimicrobial agent (7) can be sufficient to kill or inhibit growth ofmicroorganisms in contact with a polymeric tubular conduit wall externalsurface (8) of the polymeric tubular conduit wall (2).

Now referring primarily to FIG. 5 through FIG. 7, which illustrateanother particular embodiment of a polymeric tubular conduit (1)including a polymeric tubular conduit wall (2) having an outer tubularlayer (3) coaxially overlaying an inner tubular layer (4) which definesa continuous tubular passage (5) along a polymeric tubular conduitlength (6) of the polymeric tubular conduit (1), whereby the innertubular layer (4) includes an amount of antimicrobial agent (7). Theamount of antimicrobial agent (7) can be sufficient to kill or inhibitgrowth of microorganisms in contact with a polymeric tubular conduitwall internal surface (9) of the polymeric tubular conduit wall (2).

The term “polymeric tubular conduit” for the purposes of the presentinvention means a tubular conduit formed from one or more polymericmaterials. Typically, but not necessarily, the tubular conduit can havea generally circular cross-section.

The term “polymeric material” for the purposes of the present inventionmeans one or more thermoplastic polymers which can be heated andreformed, and without limitation to the breadth of the forgoing, caninclude as illustrative examples: thermoplastic elastomers such asstyrene block copolymers, polyolefin blends, elastomeric alloys,thermoplastic polyurethanes, thermoplastic copolyesters, thermoplasticpolyamides, polypropylene, polyethylene, high density polyethylene, lowdensity polyethylene, polyethylene terephthalate,poly-1,4-cyclohexanedimethylene terephthalate, polyethylene2,6-naphthalate bibenzoate, polyolefin, polyvinylidene fluoride,polyethylene 2,6-naphthalate, acrylonitrile butadiene styrene,polyvinylchloride, polyether block amide, or the like, or combinationsthereof.

The term “antimicrobial agent” for the purposes of the present inventionmeans an agent which can be combined with a polymeric material insufficient amounts to kill or inhibit growth of microorganisms incontact with the polymeric material.

The terms “combining, combined, or combination” for the purposes of thepresent invention mean putting two or more materials together. Suchmethods can include, but are not limited to, mixing, blending,commingling, concocting, homogenizing, incorporating, intermingling,fusing, joining, shuffling, stirring, coalescing, integrating,confounding, uniting, or the like, or combinations thereof.

The term “microorganism” for the purposes of the present invention meansany organism of microscopic or submicroscopic size, whether a virus, asingle cell organism, or a multicellular organism. Without limitation tothe breadth of the foregoing, microorganisms can include viruses;prokaryotes, such as bacteria and archaea; eukaryotes, such as protists,fungi, plants, and animals; or combinations thereof.

Now referring primarily to FIG. 4 and FIG. 7, the polymeric tubularconduit wall (2) can include a polymeric tubular conduit wall thickness(10) disposed between the polymeric tubular conduit wall externalsurface (8) defined by an outer tubular layer external surface (11A) ofthe outer tubular layer (3) and the polymeric tubular conduit wallinternal surface (9) defined by an inner tubular layer internal surface(12A) of the inner tubular layer (4). As to particular embodiments, thepolymeric tubular conduit wall thickness (10) can have a range ofbetween about 0.05 millimeters to about 0.25 millimeters.

As to particular embodiments, the polymeric tubular conduit wallthickness (10) can be selected from the group including or consistingof: between about 0.05 millimeters to about 0.1 millimeters; betweenabout 0.075 millimeters to about 0.125 millimeters; between about 0.1millimeters to about 0.15 millimeters; between about 0.125 millimetersto about 0.175 millimeters; between about 0.15 millimeters to about 0.2millimeters; between about 0.175 millimeters to about 0.225 millimeters;and between about 0.2 millimeters to about 0.25 millimeters.

As to particular embodiments, the polymeric tubular conduit wallthickness (10) can be generally uniform along the polymeric tubularconduit length (6) whereas, as to other particular embodiments, thepolymeric tubular conduit wall thickness (10) can be non-uniform alongthe polymeric tubular conduit length (6), depending upon theapplication.

Again referring primarily to FIG. 4 and FIG. 7, the outer tubular layer(3) can include an outer tubular layer thickness (13) disposed betweenthe outer tubular layer external surface (11A) and an outer tubularlayer internal surface (11B). In addition, the inner tubular layer (4)can include an inner tubular layer thickness (14) disposed between aninner tubular layer external surface (12B) and the inner tubular layerinternal surface (11). As to particular embodiments, the outer and innertubular layer thicknesses (13)(14) can be generally similar along thepolymeric tubular conduit length (6) whereas, as to other particularembodiments, the outer and inner tubular layers thicknesses (13)(14) canbe dissimilar along the polymeric tubular conduit length (6).

As an illustrative example of a particular embodiment of a polymerictubular conduit wall (2) having dissimilar outer and inner tubularlayers thicknesses (13)(14), the outer tubular layer (3) can be formedfrom polyethylene terephthalate, which can impart a relatively rigid andsmooth polymeric tubular conduit wall external surface (8) to thepolymeric tubular conduit wall (2) and the inner tubular layer (4) canbe formed from polypropylene, polyolefin, or a polyolefin blend, whichcan impart flexibility to the polymeric tubular conduit wall (2). As tothis particular embodiment, the outer tubular layer thickness (13) canbe in a range of between about 10% to about 25% of the polymeric tubularconduit wall thickness (10). For example, a polymeric tubular conduitwall (2) having a polymeric tubular conduit wall thickness (10) in arange of between about 0.05 millimeters to about 0.1 millimeters caninclude an outer tubular layer (3) having an outer tubular layerthickness (13) in a range of between about 0.005 millimeters to about0.025 millimeters.

As to particular embodiments of a polymeric tubular conduit (1) wherebythe outer tubular layer (3) imparts rigidity to the polymeric tubularconduit wall external surface (8) and the inner tubular layer (4)imparts flexibility to the polymeric tubular conduit wall (2), the outertubular layer thickness (13) can be adjusted to impart a desired amountof flexibility to the polymeric tubular conduit wall (2). For example, alesser outer tubular layer thickness (13) can impart greater flexibilityto the polymeric tubular conduit wall (2) in relation to a greater outertubular layer thickness (13), which can impart lesser flexibility to thepolymeric tubular conduit wall (2).

As to particular embodiments of a polymeric tubular conduit (1) wherebythe outer tubular layer (3) includes an amount of antimicrobial agent(7), a lesser outer tubular layer thickness (13) can require a lesseramount of antimicrobial agent (7) in relation to an outer tubular layer(3) having a greater outer tubular layer thickness (13), which may lowerthe cost of production. As to particular embodiments, such as one-timeuse or disposable polymeric tubular conduits (1), a lesser cost ofproduction may be desirable.

As to particular embodiments of the polymeric tubular conduit wall (2),only the outer tubular layer (3) can include an amount of antimicrobialagent (7). As to other particular embodiments of the polymeric tubularconduit wall (2), only the inner tubular layer (4) can include an amountof antimicrobial agent (7). As to yet other particular embodiments ofthe polymeric tubular conduit wall (2), both the outer and inner tubularlayers (3)(4) can include corresponding amounts of antimicrobial agent(7).

Now referring primarily to FIG. 8, as to particular embodiments, thepolymeric tubular conduit wall (2) can further include one or moreintermediate layers (16) disposed between the inner and outer tubularlayers (4)(3), whereby the one or more intermediate layers (16) caninclude an amount of antimicrobial agent (7) or be void of an amount ofantimicrobial agent (7), depending upon the application.

As to particular embodiments, the outer, inner, or intermediate tubularlayer (3)(4)(16) can include an amount of antimicrobial agent (7) in arange of between about 0.01% to about 15% by weight of the correspondingouter, inner, or intermediate tubular layer (3)(4)(16), depending uponthe antimicrobial agent (7), the application, or combinations thereof.

As to particular embodiments, the amount of antimicrobial agent (7) canbe selected from the group including or consisting of: between about0.01% to about 1% by weight of the corresponding outer, inner, orintermediate tubular layer (3)(4)(16); between about 0.5% to about 1.5%by weight of the corresponding outer, inner, or intermediate tubularlayer (3)(4)(16);

between about 1% to about 2% by weight of the corresponding outer,inner, or intermediate tubular layer (3)(4)(16); between about 1.5% toabout 2.5% by weight of the corresponding outer, inner, or intermediatetubular layer (3)(4)(16); between about 2% to about 3% by weight of thecorresponding outer, inner, or intermediate tubular layer (3)(4)(16);between about 2.5% to about 3.5% by weight of the corresponding outer,inner, or intermediate tubular layer (3)(4)(16); between about 3% toabout 4% by weight of the corresponding outer, inner, or intermediatetubular layer (3)(4)(16); between about 3.5% to about 15% 4.5% by weightof the corresponding outer, inner, or intermediate tubular layer(3)(4)(16); between about 4% to about 5% by weight of the correspondingouter, inner, or intermediate tubular layer (3)(4)(16); between about4.5% to about 5.5% by weight of the corresponding outer, inner, orintermediate tubular layer (3)(4)(16); between about 5% to about 6% byweight of the corresponding outer, inner, or intermediate tubular layer(3)(4)(16); between about 5.5% to about 6.5% by weight of thecorresponding outer, inner, or intermediate tubular layer (3)(4)(16);between about 6% to about 7% by weight of the corresponding outer,inner, or intermediate tubular layer (3)(4)(16); between about 6.5% toabout 7.5% by weight of the corresponding outer, inner, or intermediatetubular layer (3)(4)(16); between about 7% to about 8% by weight of thecorresponding outer, inner, or intermediate tubular layer (3)(4)(16);between about 7.5% to about 8.5% by weight of the corresponding outer,inner, or intermediate tubular layer (3)(4)(16); between about 8% toabout 9% by weight of the corresponding outer, inner, or intermediatetubular layer (3)(4)(16); between about 8.5% to about 9.5% by weight ofthe corresponding outer, inner, or intermediate tubular layer(3)(4)(16); between about 9% to about 10% by weight of the correspondingouter, inner, or intermediate tubular layer (3)(4)(16); between about9.5% to about 10.5% by weight of the corresponding outer, inner, orintermediate tubular layer (3)(4)(16); between about 10% to about 11% byweight of the corresponding outer, inner, or intermediate tubular layer(3)(4)(16); between about 10.5% to about 11.5% by weight of thecorresponding outer, inner, or intermediate tubular layer (3)(4)(16);between about 11% to about 12% by weight of the corresponding outer,inner, or intermediate tubular layer (3)(4)(16); between about 11.5% toabout 12.5% by weight of the corresponding outer, inner, or intermediatetubular layer (3)(4)(16); between about 12% to about 13% by weight ofthe corresponding outer, inner, or intermediate tubular layer(3)(4)(16); between about 12.5% to about 13.5% by weight of thecorresponding outer, inner, or intermediate tubular layer (3)(4)(16);between about 13% to about 14% by weight of the corresponding outer,inner, or intermediate tubular layer (3)(4)(16); between about 13.5% toabout 14.5% by weight of the corresponding outer, inner, or intermediatetubular layer (3)(4)(16); and between about 14% to about 15% by weightof the corresponding outer, inner, or intermediate tubular layer(3)(4)(16).

As to particular embodiments, the antimicrobial agent (7) can have amedian particle size distribution (D50) in a range of between about 0.5micrometers to about 15 micrometers. As to other particular embodiments,the antimicrobial agent (7) can have a median particle size distribution(D50) in a range of between about 3 micrometers to about 10 micrometers.

As to particular embodiments, an antimicrobial agent (7) having a lessermedian particle size distribution (D50), for example a median particlesize distribution (D50) of less than 1.8 micrometers, can havesubstantially greater antimicrobial activity at a similar loading inrelation to an antimicrobial agent (7) having a greater median particlesize distribution (D50), which may result from uniformity ofdistribution within the corresponding outer, inner, or intermediatetubular layer (3)(4)(16) or from an increased rate of release of theantimicrobial agent (7) within the corresponding outer, inner, orintermediate tubular layer (3)(4)(16).

As to particular embodiments, the antimicrobial agent (7) can include anamount of elemental silver or silver ions (collectively “silver”). As anillustrative example, elemental silver can take the form ofnanoparticles, which may be obtained from Bio-Gate AG, NeumeyerstraBe28-34, 90411 Nurnberg, Germany. As an illustrative example, silver ionscan take the form of silver-containing zirconium phosphates, which maybe obtained from Milliken & Company, PO Box 1926, Spartanburg, S.C.29303, United States, or can take the form of silver-containing glasses,which may be obtained from Ciba Specialty Chemicals, Klybeckstrasse 141,CH-4002 Basel, Switzerland, or can take the form of silver-containingzeolites (microporous carriers), which may be obtained from Sciessent,60 Audubon Road, Wakefield, Mass. 01880, United States.

As to particular embodiments whereby the antimicrobial agent (7)includes silver-containing zeolites, the amount of silver ions in thezeolites can be in a range of between about 0.5% to about 20% by weightof the zeolites.

As to other embodiments whereby the antimicrobial agent (7) includessilver-containing zeolites, the amount of silver ions in the zeolites(such as Product Nos. AJ 10D or II 10D, both of which may be obtainedfrom Sciessent, 60 Audubon Road, Wakefield, Mass. 01880, United States)can be around 2.5% by weight of the zeolites.

As to particular embodiments, the outer, inner, or intermediate tubularlayer (3)(4)(16) can include an amount of silver sufficient to kill orinhibit growth of microorganisms. As to particular embodiments, theamount of silver can be in a range of between about 0.01% to about 2% byweight of the corresponding outer, inner, or intermediate tubular layer(3)(4)(16).

As an illustrative example, a polymeric tubular conduit (1) can includean outer tubular layer (3) formed from polyethylene terephthalate havingan amount of silver in a range of between about 0.5% to about 2% byweight of the outer tubular layer (3).

As to particular embodiments, the antimicrobial agent (7) can include acombination of elements or elemental ions. As an illustrative example,the elements or elemental ions can include silver and zinc. As toparticular embodiments, the combination of silver and zinc can includegenerally similar amounts of silver and zinc.

As to other particular embodiments, the combination of silver and zinccan include a greater amount of silver and a lesser amount of zinc. Asto yet other particular embodiments, the combination of zinc and silvercan include a lesser amount of silver and a greater amount of zinc.

As to particular embodiments, the combination of silver and zinc canhave a ratio in a range of between about 1:1 to about 3:1. As anillustrative example, a polymeric tubular conduit (1) can include anouter tubular layer (3) formed from polyethylene terephthalate having acombination of silver and zinc in a ratio of about 2:1, whereby thecombination of silver and zinc can be in a range of between about 0.5%to about 2% by weight of the outer tubular layer (3).

As to other particular embodiments, the combination of silver and zinccan have a ratio of between about 1:1 to about 1:3. As an illustrativeexample, a polymeric tubular conduit (1) can include an outer tubularlayer (3) formed from polyethylene terephthalate having a combination ofsilver and zinc in a ratio of about 1:2, whereby the combination ofsilver and zinc can be in a range of between about 0.5% to about 2% byweight of the outer tubular layer (3).

Now referring primarily to FIG. 1A, as to particular embodiments, thepolymeric tubular conduit (1) can form a drinking straw (17), forexample a drinking straw (17) including a drinking straw wall (18)having a drinking straw outer tubular layer (19) coaxially overlaying adrinking straw inner tubular layer (20) which defines a drinking strawcontinuous tubular passage (21) along a drinking straw length (22) ofthe drinking straw (17) through which fluids can be drawn; whereby thedrinking straw outer tubular layer (19) includes an amount ofantimicrobial agent (7). The amount of antimicrobial agent (7) can besufficient to kill or inhibit growth of microorganisms which contact adrinking straw wall external surface (23) of the drinking straw wall(18).

The polymeric tubular conduit (1) can be compatible with drinking straws(17) of all common dimensions. Typically, but not necessarily, adrinking straw (17) can have a drinking straw wall thickness (24) in arange of between about 0.4 millimeters to about 0.8 millimeters, with adrinking straw interior diameter (25) in a range of between about 1.6millimeters to about 9.5 millimeters; however, embodiments of thepolymeric tubular conduit (1) for use as a drinking straw (17) can havea lesser or greater drinking straw wall thickness (24) or drinking strawinterior diameter (25), depending upon the application.

Typically, but not necessarily, embodiments of the polymeric tubularconduit (1) for use as a drinking straw (17) can have a drinking strawlength (22) in a range of between about 75 millimeters to about 300millimeters; however, embodiments of the polymeric tubular conduit (1)for use as a drinking straw (17) can have a lesser or greater drinkingstraw length (22), depending upon the application. As an illustrativeexample, embodiments of the polymeric tubular conduit (1) for use as adrinking straw (17) can have a drinking straw length (22) in a range ofbetween about 190 millimeters to about 197 millimeters.

Now referring primarily to FIG. 1B, as to other particular embodiments,the polymeric tubular conduit (1) can form medical tubing (26), forexample medical tubing (26) including a medical tubing wall (27) havinga medical tubing outer tubular layer (28) coaxially overlaying a medicaltubing inner tubular layer (29) which defines a medical tubingcontinuous tubular passage (30) along a medical tubing length (31) ofthe medical tubing (26) through which fluids can be drawn; whereby themedical tubing outer tubular layer (28) includes an amount ofantimicrobial agent (7). The amount of antimicrobial agent (7) can besufficient to kill or inhibit growth of microorganisms which contact amedical tubing wall external surface (32) of the medical tubing wall(27).

EXAMPLES

Direct Inoculation Assay

Efficacy of first, second, and third polymeric tubular conduits (1),each having an inner tubular layer (4) including an amount ofantimicrobial agent (7), was tested again Escherichia coli by a directinoculation assay, whereby each polymeric tubular conduit internalsurface (9) was inoculated with 3.0×10⁵ CFU/mL of Escherichia coli andincubated for 24 hours in a sealed container with humidity. Followingthe incubation, each polymeric tubular conduit (1) was enumerated,whereby the first, second, and third polymeric tubular conduits (1) hadcorresponding 99.9999%, 99.999%, and 99.999% percent reductions inCFU/mL of Escherichia coli. For comparison, the positive control, whichwas void of an amount of antimicrobial agent (7), had a 6233% percentincrease in CFU/mL of Escherichia coli following the 24 hour incubation.

Zone of Inhibition Test

As an additional example, efficacy of the polymeric tubular conduit (1)having an outer, inner, or intermediate tubular layer (3)(4)(16)including an amount of antimicrobial agent (7) can be tested againstEscherichia coli (Gram-negative bacteria), Staphylococcus aureus(Gram-positive bacteria), Aspergillus niger (fungi), Cladosporiumcladosporioides (fungi), or Trichoderma sp. (fungi) by a zone ofinhibition test, as follows.

Test Samples

Control: a polymeric tubular conduit (1) including an outer tubularlayer (3) of polyethylene terephthalate having an outer tubular layerthickness (13) thickness of about 0.127 millimeters which does notinclude an amount of antimicrobial agent (7) and an inner tubular layer(4) of polyoefin having an inner tubular layer thickness (14) of about0.381 millimeters which does not include an amount of antimicrobialagent (7).

Test Sample 1: a polymeric tubular conduit (1) including an outertubular layer (3) of polyethylene terephthalate having an outer tubularlayer thickness (13) thickness of about 0.127 millimeters which includesan amount of antimicrobial agent (7) comprising silver in an amount ofabout 0.5% by weight of the outer tubular later (3) and an inner tubularlayer (4) of polyoefin having an inner tubular layer thickness (14) ofabout 0.381 millimeters which does not include an amount ofantimicrobial agent (7).Test Sample 2: a polymeric tubular conduit (1) including an outertubular layer (3) of polyethylene terephthalate having an outer tubularlayer thickness (13) thickness of about 0.127 millimeters which includesan amount of antimicrobial agent (7) comprising silver in an amount ofabout 1% by weight of the outer tubular later (3) and an inner tubularlayer (4) of polyoefin having an inner tubular layer thickness (14) ofabout 0.381 millimeters which does not include an amount ofantimicrobial agent (7).Test Sample 3: a polymeric tubular conduit (1) including an outertubular layer (3) of polyethylene terephthalate having an outer tubularlayer thickness (13) thickness of about 0.127 millimeters which includesan amount of antimicrobial agent (7) comprising silver in an amount ofabout 2% by weight of the outer tubular later (3) and an inner tubularlayer (4) of polyoefin having an inner tubular layer thickness (14) ofabout 0.381 millimeters which does not include an amount ofantimicrobial agent (7).Test Sample 4: a polymeric tubular conduit (1) including an outertubular layer (3) of polyethylene terephthalate having an outer tubularlayer thickness (13) thickness of about 0.127 millimeters which includesan amount of antimicrobial agent (7) comprising silver and zinc in aratio of about 2:1 and in an amount of about 0.5% by weight of the outertubular later (3) and an inner tubular layer (4) of polyoefin having aninner tubular layer thickness (14) of about 0.381 millimeters which doesnot include an amount of antimicrobial agent (7).Test Sample 5: a polymeric tubular conduit (1) including an outertubular layer (3) of polyethylene terephthalate having an outer tubularlayer thickness (13) thickness of about 0.127 millimeters which includesan amount of antimicrobial agent (7) comprising silver and zinc in aratio of about 2:1 and in an amount of about 1% by weight of the outertubular later (3) and an inner tubular layer (4) of polyoefin having aninner tubular layer thickness (14) of about 0.381 millimeters which doesnot include an amount of antimicrobial agent (7).Test Sample 6: a polymeric tubular conduit (1) including an outertubular layer (3) of polyethylene terephthalate having an outer tubularlayer thickness (13) thickness of about 0.127 millimeters which includesan amount of antimicrobial agent (7) comprising silver and zinc in aratio of about 2:1 and in an amount of about 2% by weight of the outertubular later (3) and an inner tubular layer (4) of polyoefin having aninner tubular layer thickness (14) of about 0.381 millimeters which doesnot include an amount of antimicrobial agent (7).Test Method for Escherichia coli or Staphylococcus aureus

Basal Medium Eagle (BME) with Earle's salts and L-glutamine can bemodified with calf/serum (10%) and 1.5% agar prior to being dispensed(15 mL) into Petri dishes. The agar-containing Petri dishes can beallowed to surface dry prior to inoculation with a lawn of Escherichiacoli or Staphylococcus aureus. The inoculant can be prepared fromBactrol Discs available from Fisher

Scientific which can be reconstituted as per the manufacturer'sdirections. Immediately after inoculation, one or more polymeric tubularconduits (1) can be placed on the surface of the agar. The Petri dishescan be incubated for about 24 hours at about 37° C. Following, the zoneof inhibition can be measured and a corrected zone of inhibition can becalculated (corrected zone of inhibition equals zone of inhibition minusdiameter of test material in contact with the agar).

Test Results

Escherichia coli. The results can show no zone of inhibition associatedwith the control polymeric tubular conduit (1) and a zone of inhibitionof about 0.5 millimeters around test samples 1 and 4, a zone ofinhibition of about 5 millimeters around test samples 2 and 5, and azone of inhibition of about 10 millimeters around test samples 3 and 6.Staphylococcus aureus. The results can show no zone of inhibitionassociated with the control polymeric tubular conduit (1) and a zone ofinhibition of about 0.5 millimeters around test samples 1 and 4, a zoneof inhibition of about 5 millimeters around test samples 2 and 5, and azone of inhibition of about 10 millimeters around test samples 3 and 6.Test Method for Aspergillus niger, Cladosporium cladosporioides,orTrichoderma sp.Sabouraud dextrose agar media (Biolife Vole Monza), pH 5.6, can be usedfor antifungal screening. Agar-containing Petri dishes can be allowed tosurface dry prior to inoculation with a lawn of Aspergillus niger,Cladosporium cladosporioides, or Trichoderma sp. Immediately afterinoculation, polymeric tubular conduits (1) can be placed on the surfaceof the agar. The Petri dishes can be incubated for about 72 hours atabout 37° C. Following, the zone of inhibition can be measured and acorrected zone of inhibition can be calculated (corrected zone ofinhibition equals zone of inhibition minus diameter of test material incontact with the agar).Test ResultsAspergillus niger. The results can show no zone of inhibition associatedwith the control polymeric tubular conduit (1) and a zone of inhibitionof about 2 millimeters around test samples 1 and 4, a zone of inhibitionof about 5 millimeters around test samples 2 and 5, and a zone ofinhibition of about 13 millimeters around test samples 3 and 6.Cladosporium cladosporioides. The results can show no zone of inhibitionassociated with the control polymeric tubular conduit (1) and a zone ofinhibition of about 4 millimeters around test samples 1 and 4, a zone ofinhibition of about 8 millimeters around test samples 2 and 5, and azone of inhibition of about 14 millimeters around test samples 3 and 6.Trichoderma sp. The results can show no zone of inhibition associatedwith the control polymeric tubular conduit (1) and a zone of inhibitionof about 3 millimeters around test samples 1 and 4, a zone of inhibitionof about 9 millimeters around test samples 2 and 5, and a zone ofinhibition of about 15 millimeters around test samples 3 and 6.

A method of making a polymeric tubular conduit (1) can include providinga polymeric tubular conduit wall (2) having an outer tubular layer (3)coaxially overlaying an inner tubular layer (4) which defines acontinuous tubular passage (5) along a polymeric tubular conduit length(6) of the polymeric tubular conduit (1), whereby the outer tubularlayer (3) includes an amount of antimicrobial agent (7).

As to particular embodiments, the method can further include forming theinner tubular layer (4) from a first polymeric material (33) and formingthe outer tubular layer (3) from a second polymeric material (34),whereby the amount of antimicrobial agent (7) can be combined with thesecond polymeric material (34) to provide the outer tubular layer (3)including an amount of antimicrobial agent (7).

Another method of making a polymeric tubular conduit (1) can includeproviding a polymeric tubular conduit wall (2) having an outer tubularlayer (3) coaxially overlaying an inner tubular layer (4) which definesa continuous tubular passage (5) along a polymeric tubular conduitlength (6) of the polymeric tubular conduit (1), whereby the innertubular layer (4) includes an amount of antimicrobial agent (7).

As to particular embodiments, the method can further include forming theinner tubular layer (4) from a first polymeric material (33) and formingthe outer tubular layer (3) from a second polymeric material (34),whereby the amount of antimicrobial agent (7) can be combined with thefirst polymeric material (33) to provide the inner tubular layer (4)including an amount of antimicrobial agent (7).

As to particular embodiments, the method can further include coextrudingthe first and second polymeric materials (33)(34) to form the polymerictubular conduit (1) including the polymeric tubular conduit wall (2)having the outer tubular layer (3) coaxially overlaying the innertubular layer (4).

As to particular embodiments, the method can further include cooling thecoextruded polymeric tubular conduit (1) to a temperature below asoftening point of the first and second polymeric materials (33)(34). Asto particular embodiments, the cooled polymeric tubular conduit (1) canprovide a drinking straw (17). As to other particular embodiments, thecooled polymeric tubular conduit (1) can provide medical tubing (26).

As to particular embodiments, the method can further include cutting thecooled polymeric tubular conduit (1) across the polymeric tubularconduit length (6) to provide a plurality of discrete polymeric tubularconduits (1). As to particular embodiments, the plurality of discretepolymeric tubular conduits (1) can provide a plurality of discretedrinking straws (17).

Now referring primarily to FIG. 6 through FIG. 8, the first and secondpolymeric materials (33)(34) (and, as to particular embodiments,additional polymeric materials (35) which can form one or moreintermediate layers (16)) can be provided in the form of nurdles (36)which generally take the form of small granules or beads (also referredto as “resin”). Each of the first and second polymeric materials(33)(34) (and, as to particular embodiments, additional polymericmaterials (36) which can form one or more intermediate layers (16)) canfurther include additives (37), such as plasticizers, fillers, pigments,colorants, ultraviolet radiation inhibitors, or the like, orcombinations thereof, which can be included during production of thefirst and second polymeric materials (33)(34) (and, as to particularembodiments, additional polymeric materials (35) which can form one ormore intermediate layers (16)) or can be provided as a liquid(s) or as asolid(s) which can be combined with the nurdles (36).

The antimicrobial agent (7) can be combined with the first or secondpolymeric materials (33)(34) (or, as to particular embodiments,additional polymeric materials (35) which can form one or moreintermediate layers (16)) in the production of the nurdles (36) orcombined as a discrete additive to the nurdles (36) to achieve aconcentration of the antimicrobial agent (7).

Again referring primarily to FIG. 6 through FIG. 8, for coextrusion, thefirst and second polymeric materials (33)(34) (and, as to particularembodiments, additional polymeric materials (35) which can form one ormore intermediate layers (16)), each in the form of nurdles (36), caneach be disposed in a hopper (38) of corresponding first and secondextruders (39)(40) (and, as to particular embodiments, additionalextruders (41) which can receive the additional polymeric materials (35)which can form one or more intermediate layers (16)), whereby thenurdles (36) can be fed under influence of gravity through a feed throat(42) of the hopper (38) proximate a barrel rear end (43) of a barrel(44). A screw (45) rotatably journaled in the barrel (44) can contactthe nurdles (36) entering the barrel rear end (43). A driver (46)operates to rotate the screw (45) inside the barrel (44), forcing thenurdles (36) toward a barrel front end (47) of the barrel (44). The rateat which the screw (45) rotates in the barrel (44) can be adjusted, butgenerally the screw (45) rotates up to about 120 revolutions per minute;however, the invention need not be so limited, as the screw (45) canrotate at any rate sufficient to move the nurdles (36) from the barrelrear end (43) toward the barrel front end (47), including rates lesseror greater than 120 revolutions per minute, depending upon theapplication. As to particular embodiments, the screw (45) can be drivenat a continuous rate or at a variable rate, depending upon theapplication.

Now referring primarily to FIG. 6, as to each extruder (39)(40)(41), aheater (48) can be coupled to the barrel (44) to heat the barrel (44) toa desired temperature. One or more temperature sensors (49) can bedisposed in relation to a barrel wall (50) to sense the temperaturealong the length of the barrel (44), which can be controlled to achievethe melt point of the nurdles (36) (the temperature at which the nurdles(36) begin to turn from a solid to a liquid, also referred to as“molten” polymeric material).

The melt point can vary greatly between different polymeric materials(33)(34)(35) but typically occurs within a range from between about 200°C. (392° F.) to about 275° C. (527° F.); however, particular polymericmaterials (33)(34)(35) may have a melt point which occurs at a lesser orgreater temperature. Further, the melt point can vary depending uponadditives (37) introduced.

A heating profile can be set for the barrel (44) in which one or moretemperature-controlled heater zones (51) gradually increase thetemperature of the barrel (44) from the barrel rear end (43) to thebarrel front end (47). This can allow the nurdles (36) of the first andsecond polymeric materials (33)(34) (and, as to particular embodiments,additional polymeric materials (35) which can form one or moreintermediate layers (16)) to melt gradually as they are forced along thelength of the barrel (44) toward the barrel front end (47).

The screw (45) acting on the nurdles (36) can generate an amount ofpressure, friction, or combinations thereof, which can generate anadditional amount of heat. The heat of the pressure, friction, orcombinations thereof, can be sufficient to achieve or maintain the meltpoint of the first and second polymeric materials (33)(34) (and, as toparticular embodiments, additional polymeric materials (35) which canform one or more intermediate layers (16)) inside the correspondingbarrel (44). Each extruder (39)(40)(41) can further include a coolingelement (52), such as a fan or water jacket, to maintain the temperatureat or below a temperature set point.

Now referring primarily to FIG. 8, the molten first and second polymericmaterials (33)(34) (and, as to particular embodiments, additional moltenpolymeric materials (35) which can form one or more intermediate layers(16)) can egress from the corresponding barrel (44) and can be forcedthrough corresponding one or more screens (53) to remove anycontaminants in the molten polymeric material (33)(34)(35). The one ormore screens (53) can be reinforced by a breaker plate (54), which cantake the form of a metal disk having a plurality bores communicatingbetween opposed sides. The one or more screens (53) and breaker plate(54) acting on the corresponding molten polymeric material (33)(34)(35)can generate a substantial back pressure of the polymeric material(33)(34)(35) in the corresponding barrel (44). The configuration of theone or more screens (53) with respect to overall dimensional relations,wire size, total open area, or other parameters, and the configurationof the breaker plate (54) with respect to overall dimensional relations,bore size, total open area, or other parameters, can be adjusted tocorrespondingly adjust the amount of back pressure in the barrel (44) asrequired for uniform melting and proper mixing of the correspondingpolymeric material (33)(34)(35). The back pressure can vary greatlydepending upon the polymeric material (33)(34)(35), or additive,utilized, the configuration of the polymeric tubular conduit (1) beingproduced, or other parameters, typically occurring in a range of betweenabout 1,000 psi (about 7 megapascals) to about 10,000 psi (about 70megapascals); although particular applications may generate a lesser orgreater back pressure. The breaker plate (54) can also function toconvert “rotational memory” of the molten polymeric material(33)(34)(35) into “longitudinal memory” of the molten polymeric material(3)(34)(35).

Again referring primarily to FIG. 8, which provides an illustrativeexample of molten first and second polymeric materials (33)(34) passingthrough corresponding breaker plates (54) into a die (55) having a firstdie passage (56) which receives the first polymeric material (33) fromthe first extruder (39) and a second die passage (57) which receives thesecond polymeric material (34) from the second extruder (40). The firstdie passage (56) can be configured to generate the inner tubular layer(4) of the polymeric tubular conduit (1). The second die passage (57)can be configured to co-axially generate the outer tubular layer (3)about the inner tubular layer (4) of the polymeric tubular conduit (1)to provide the configurations of the polymeric tubular conduit (1) abovedescribed, including embodiments of the drinking straw (17) and themedical tubing (26).

Now referring primarily to FIG. 6 and FIG. 7, as the polymeric tubularconduit (1) (also referred to as an “extrudate”), including the innertubular layer (4) formed from the first polymeric material (33) and theouter tubular layer (3) formed from the second polymeric material (34),egresses from the die (55), the extrudate can be cooled, for example bybeing drawn through a bath (58) containing an amount of coolant (59),which can typically, but not necessarily, be water. In the production ofthe polymeric tubular conduit (1) in accordance with the invention, thebath (58) can take the form of an elongate enclosure (60) having anextrudate inlet (61) mounted in relation to an inlet side (62) of thebath (58) and an extrudate outlet (63) mounted in relation to an outletside (64) of the bath (58). The extrudate inlet (62) and the extrudateoutlet (63) can correspondingly include an inlet seal (65) and an outletseal (66) configured to sufficiently engage the polymeric tubularconduit wall external surface (8) to maintain a coolant level (67)within the bath (58) between the extrudate inlet (61) and the extrudateoutlet (63) through which the polymeric tubular conduit (1) can be drawnfor cooling. The remaining volume of the bath (58) can provide aheadspace (68) within the bath (58).

Now referring primarily to FIG. 6, a vacuum generator (69) can operateto reduce pressure within the bath (58) in relation to the ambientpressure outside the bath (58), which can act at the inlet seal (65) andthe outlet seal (66) to draw an amount of coolant (59) toward the bathinterior volume, which can act on the still-molten polymeric tubularconduit (1) to counter a tendency toward collapse. Once cooled, thepolymeric tubular conduit (1) can be wound on a spool (70), or cut intolengths for use as a drinking straw (17), medical tubing (26), orotherwise used or stored.

Now referring primarily to FIG. 1A and FIG. 1B, a method of using apolymeric tubular conduit (1) can include obtaining the polymerictubular conduit (1) including a polymeric tubular conduit wall (2)having an outer tubular layer (3) coaxially overlaying an inner tubularlayer (4) which defines a continuous tubular passage (5) along apolymeric tubular conduit length (6) of the polymeric tubular conduit(1), whereby the outer tubular layer (3) comprises an amount ofantimicrobial agent (7); and drawing fluids through the continuoustubular passage (5). The amount of antimicrobial agent (7) can besufficient to kill or inhibit growth of microorganisms which contact apolymeric tubular conduit wall external surface (8) of the polymerictubular conduit wall (2). As to particular embodiments, the polymerictubular conduit (1) can provide a drinking straw (17) (as shown in FIG.1A). As to other particular embodiments, the polymeric tubular conduit(1) can provide medical tubing (26) (as shown in FIG. 1B).

As to other particular embodiments, a method of using a polymerictubular conduit (1) can include obtaining the polymeric tubular conduit(1) including a polymeric tubular conduit wall (2) having an outertubular layer (3) coaxially overlaying an inner tubular layer (4) whichdefines a continuous tubular passage (5) along a polymeric tubularconduit length (6) of the polymeric tubular conduit (1), whereby theinner tubular layer (4) comprises an amount of antimicrobial agent (7);and drawing fluids through the continuous tubular passage (5). Theamount of antimicrobial agent (7) can be sufficient to kill or inhibitgrowth of microorganisms which contact a polymeric tubular conduit wallinternal surface (9) of the polymeric tubular conduit wall (2). As toparticular embodiments, the polymeric tubular conduit (1) can provide adrinking straw (17). As to other particular embodiments, the polymerictubular conduit (1) can provide medical tubing (26).

As can be easily understood from the foregoing, the basic concepts ofthe present invention may be embodied in a variety of ways. Theinvention involves numerous and varied embodiments of an antimicrobialstraw and methods for making and using such antimicrobial straws,including the best mode.

As such, the particular embodiments or elements of the inventiondisclosed by the description or shown in the figures or tablesaccompanying this application are not intended to be limiting, butrather exemplary of the numerous and varied embodiments genericallyencompassed by the invention or equivalents encompassed with respect toany particular element thereof In addition, the specific description ofa single embodiment or element of the invention may not explicitlydescribe all embodiments or elements possible; many alternatives areimplicitly disclosed by the description and figures.

It should be understood that each element of an apparatus or each stepof a method may be described by an apparatus term or method term. Suchterms can be substituted where desired to make explicit the implicitlybroad coverage to which this invention is entitled. As but one example,it should be understood that all steps of a method may be disclosed asan action, a means for taking that action, or as an element which causesthat action. Similarly, each element of an apparatus may be disclosed asthe physical element or the action which that physical elementfacilitates. As but one example, the disclosure of an “inhibitor” shouldbe understood to encompass disclosure of the act of “inhibiting”—whetherexplicitly discussed or not—and, conversely, were there effectivelydisclosure of the act of “inhibiting”, such a disclosure should beunderstood to encompass disclosure of an “inhibitor” and even a “meansfor inhibiting”. Such alternative terms for each element or step are tobe understood to be explicitly included in the description.

In addition, as to each term used it should be understood that unlessits utilization in this application is inconsistent with suchinterpretation, common dictionary definitions should be understood toincluded in the description for each term as contained in the RandomHouse Webster's Unabridged Dictionary, second edition, each definitionhereby incorporated by reference.

All numeric values herein are assumed to be modified by the term“about”, whether or not explicitly indicated. For the purposes of thepresent invention, ranges may be expressed as from “about” oneparticular value to “about” another particular value. When such a rangeis expressed, another embodiment includes from the one particular valueto the other particular value. The recitation of numerical ranges byendpoints includes all the numeric values subsumed within that range. Anumerical range of one to five includes for example the numeric values1, 1.5, 2, 2.75, 3, 3.80, 4, 5, and so forth. It will be furtherunderstood that the endpoints of each of the ranges are significant bothin relation to the other endpoint, and independently of the otherendpoint. When a value is expressed as an approximation by use of theantecedent “about,” it will be understood that the particular valueforms another embodiment. The term “about” generally refers to a rangeof numeric values that one of skill in the art would consider equivalentto the recited numeric value or having the same function or result.Similarly, the antecedent “substantially” means largely, but not wholly,the same form, manner or degree and the particular element will have arange of configurations as a person of ordinary skill in the art wouldconsider as having the same function or result. When a particularelement is expressed as an approximation by use of the antecedent“substantially,” it will be understood that the particular element formsanother embodiment.

Moreover, for the purposes of the present invention, the term “a” or“an” entity refers to one or more of that entity unless otherwiselimited. As such, the terms “a” or “an”, “one or more” and “at leastone” can be used interchangeably herein.

Thus, the applicant(s) should be understood to claim at least: i) eachof the antimicrobial straws herein disclosed and described, ii) therelated methods disclosed and described, iii) similar, equivalent, andeven implicit variations of each of these devices and methods, iv) thosealternative embodiments which accomplish each of the functions shown,disclosed, or described, v) those alternative designs and methods whichaccomplish each of the functions shown as are implicit to accomplishthat which is disclosed and described, vi) each feature, component, andstep shown as separate and independent inventions, vii) the applicationsenhanced by the various systems or components disclosed, viii) theresulting products produced by such systems or components, ix) methodsand apparatuses substantially as described hereinbefore and withreference to any of the accompanying examples, x) the variouscombinations and permutations of each of the previous elementsdisclosed.

The background section of this patent application provides a statementof the field of endeavor to which the invention pertains. This sectionmay also incorporate or contain paraphrasing of certain United Statespatents, patent applications, publications, or subject matter of theclaimed invention useful in relating information, problems, or concernsabout the state of technology to which the invention is drawn toward. Itis not intended that any United States patent, patent application,publication, statement or other information cited or incorporated hereinbe interpreted, construed or deemed to be admitted as prior art withrespect to the invention.

The claims set forth in this specification, if any, are herebyincorporated by reference as part of this description of the invention,and the applicant expressly reserves the right to use all of or aportion of such incorporated content of such claims as additionaldescription to support any of or all of the claims or any element orcomponent thereof, and the applicant further expressly reserves theright to move any portion of or all of the incorporated content of suchclaims or any element or component thereof from the description into theclaims or vice-versa as necessary to define the matter for whichprotection is sought by this application or by any subsequentapplication or continuation, division, or continuation-in-partapplication thereof, or to obtain any benefit of, reduction in feespursuant to, or to comply with the patent laws, rules, or regulations ofany country or treaty, and such content incorporated by reference shallsurvive during the entire pendency of this application including anysubsequent continuation, division, or continuation-in-part applicationthereof or any reissue or extension thereon.

Additionally, the claims set forth in this specification, if any, arefurther intended to describe the metes and bounds of a limited number ofthe preferred embodiments of the invention and are not to be construedas the broadest embodiment of the invention or a complete listing ofembodiments of the invention that may be claimed. The applicant does notwaive any right to develop further claims based upon the description setforth above as a part of any continuation, division, orcontinuation-in-part, or similar application.

The invention claimed is:
 1. A method of making a polymeric tubularconduit, comprising: forming a polymeric tubular conduit wall having anouter tubular layer coaxially overlaying an inner tubular layer whichdefines a continuous tubular passage along a polymeric tubular conduitlength of said polymeric tubular conduit; wherein said outer tubularlayer comprises an amount of antimicrobial agent; and wherein saidamount of antimicrobial agent is characterized by at least one of thefollowing: (i) wherein said amount of antimicrobial agent is not greaterthan about 3% by weight of said inner tubular layer; (ii) wherein saidantimicrobial agent has a median particle size distribution which is notless than about 0.5 micrometers; and (iii) wherein said antimicrobialagent comprises silver-containing zeolites; and wherein an amount ofsilver ions in said silver-containing zeolites is in a range of betweenabout 0.5% to about 20% by weight of said silver-containing zeolites. 2.The method of claim 1, wherein said step of forming is done by: formingsaid inner tubular layer from a first polymeric material; and formingsaid outer tubular layer from a second polymeric material, wherein saidamount of antimicrobial agent is combined with said second polymericmaterial.
 3. A method of making a polymeric tubular conduit, said methodcomprising: forming a polymeric tubular conduit wall having an outertubular layer coaxially overlaying an inner tubular layer which definesa continuous tubular passage along a polymeric tubular conduit length ofsaid polymeric tubular conduit; wherein said inner tubular layercomprises an amount of antimicrobial agent; and wherein said amount ofantimicrobial agent is characterized by at least one of the following:(i) wherein said amount of antimicrobial agent is not greater than about3% by weight of said inner tubular layer; (ii) wherein saidantimicrobial agent has a median particle size distribution which is notless than about 0.5 micrometers; and (iii) wherein said antimicrobialagent comprises silver-containing zeolites; and wherein an amount ofsilver ions in said silver-containing zeolites is in a range of betweenabout 0.5% to about 20% by weight of said silver-containing zeolites. 4.The method of claim 3, wherein said step of forming is done by: formingsaid inner tubular layer from a first polymeric material; and formingsaid outer tubular layer from a second polymeric material, wherein saidamount of antimicrobial agent is combined with said first polymericmaterial.
 5. The method of claim 2, wherein said step of forming is doneby coextruding said first and second polymeric materials to form saidpolymeric tubular conduit comprising said polymeric tubular conduit wallhaving said outer tubular layer coaxially overlaying said inner tubularlayer.
 6. The method of claim 5, further comprising cooling saidcoextruded polymeric tubular conduit to a temperature below a softeningpoint of said first and second polymeric materials.
 7. The method ofclaim 6, wherein said cooled polymeric tubular conduit provides adrinking straw.
 8. The method of claim 6, wherein said cooled polymerictubular conduit provides medical tubing.
 9. The method of claim 6,further comprising: cutting said cooled polymeric tubular conduit acrosssaid polymeric tubular conduit length to provide a plurality of discretepolymeric tubular conduits.
 10. The method of claim 9, wherein saidplurality of discrete polymeric tubular conduits provides a plurality ofdiscrete drinking straws.
 11. The method of claim 1, wherein said amountof antimicrobial agent is sufficient to kill microorganisms whichcontact a polymeric tubular conduit wall external surface of saidpolymeric tubular conduit wall.
 12. The method of claim 1, wherein saidamount of antimicrobial agent is sufficient to inhibit growth ofmicroorganisms which contact a polymeric tubular conduit wall externalsurface of said polymeric tubular conduit wall.
 13. The method of claim3, wherein said amount of antimicrobial agent is sufficient to killmicroorganisms which contact a polymeric tubular conduit wall externalsurface of said polymeric tubular conduit wall.
 14. The method of claim3, wherein said amount of antimicrobial agent is sufficient to inhibitgrowth of microorganisms which contact a polymeric tubular conduit wallexternal surface of said polymeric tubular conduit wall.
 15. The methodof claim 4, further comprising: coextruding said first and secondpolymeric materials to form said polymeric tubular conduit comprisingsaid polymeric tubular conduit wall having said outer tubular layercoaxially overlaying said inner tubular layer.
 16. The method of claim15, further comprising cooling said coextruded polymeric tubular conduitto a temperature below a softening point of said first and secondpolymeric materials.
 17. The method of claim 16, wherein said cooledpolymeric tubular conduit provides a drinking straw.
 18. The method ofclaim 16, wherein said cooled polymeric tubular conduit provides medicaltubing.
 19. The method of claim 16, further comprising: cutting saidcooled polymeric tubular conduit across said polymeric tubular conduitlength to provide a plurality of discrete polymeric tubular conduits.20. The method of claim 19, wherein said plurality of discrete polymerictubular conduits provides a plurality of discrete drinking straws.